So, while some people seem to think negatively of the idea thinking I should just go the easy way, but most people actually rather like it including me even if it's just for the heck and fun of it. Using spare parts I had lying around, I'm building a fridge in the odd extra storage compartment in the panel opposite of where the spare tire is supposed to go. Not very sure what the compartment was originally meant for and it seems to be missing an actual enclosure on the inside, but oh well it'll be a fridge now! My current prototype consists of a forgotten and tossed aside 12v mini-fridge I completely took apart, the two things I love about it is how the peltier element in it really cools damn well even straight away but also has a heating mode when the switch is turned to the other side. I'm using the aluminium enclosure that was on the inside of the fridge, which when it still had some plastic above it to make it higher already was rather small, as the inside of the fridge for it's high thermalcondunctive qualities (padded with styrofoam for isolation). For now it will do, it holds two small containers of chocolade milk and my usual sandwiches, it's all it will fit for now but seeing as that is my daily lunch it's okay for a prototype. In the meanwhile I am still looking for a suitable aluminum container to replace it with, one that is bigger and higher for more storage capacity. The power will be supplied by a traction battery, a little overkill for a budget project one might think but we still had one lying around that was basically hopelessly gathering dust in the back of the garage, instead of having to recharge it manually as I am doing so now for testing purposes I hope to be able to somehow wire it up to the alternator without having them charge and discharge each other killing each other slowly or ruining anything else like the alternator itself. There seem to be nifty gadgets to control this, which will have it first charge the starting battery before charging the other one, but unfortunately these are rather expensive and I'd much rather spend the money on more important things for my car despite the 'coolness' of this project. But yeah, I'm really close to getting the first prototype completely functional, it won't win the beauty award but it will work and besides it's hidden under the cover anyways. As far as I know the space is important for the ventilation of the body, so in the end when I finish it off to look nice I will make sure to still allow for some ventilation. Will post pictures once I get around to do so.

 

See this is why i love this site, someone is always thinking up something new. It doesn't matter what anyone else thinks of a certain project. You just may have a prototype for a production refrigerator. I just bought a new chevy Silverado and it has everything but a refrigerator.

 

I've seen people make a cooler out of the locking compartment in the trunk, put some ice in and good to go. If you can power it and seal it i can see it happening.

 

And imagine it having it's own dedicated traction battery, it would pretty much always be cooling it in theory, as it's a daily driver so I'd expect the traction battery to be charged enough all of the time (if it will charge quickly enough of course). Ice will be preserved very long in theory, I don't expect it to turn out as an actual freezer but tomorrow I've got a day off so we'll see what happens and what kind of temperatures can be measured at what outside temperatures and over how much time and etc. It'll be like some sort of ice cold school-like scientific project, but with the very appreciated 'cool' benefits it actually provides.

 

Alright, zhe prototype has been 'unleashed', in a makeshift way (guesswork as to the Styrofoam isolation) but it should give an idea of the cooling capacities. Starting out with 84.2 degrees Fahrenheit (29 Celsius) roomtemperature, and letting the fridge run for about 30 minutes to both give the fridge some time and the thermometer some time to adjust. Will update with an edit as soon as the time has passed.

Edit: After 30 minutes the air temperature has dropped down to around 68 degrees Fahrenheit (20 Celsius), without the addition of ice, and the aluminum casing on the inside already feels very cold to the touch. I'm putting in a small container of chocolade milk (at room temperature) for another half a hour to determine the short term cooling capacity it has on such drinks, also going to take pictures.

Edit: Some pictures, like I said it won't with a beauty contest but it's a fully functional prototype. Can be a very easy and most inexpensive DIY by the way, all you need to have is a USB minifridge (that's right, the dirt cheap PC ones); or a lighterplug fridge for the cooling stuff and optional warming mode (or a true geek could try to assemble it himself but I believe this to be inefficient and possibly more expensive), an aluminum encasing (or copper which is even better, if you've got it lying around or feel like spending some money for it) and some Styrofoam for isolation, plus what you want to use to finish it off in style, making it something to look at and worth presenting, which I'm still going to do as well.





Edit: The temperature has continued to drop, at a slower pace now but it does keep dropping, putting a break on it for the moment but I will keep the fridge running and inspect it tonight. Next I will experiment with better isolation and possibly with some ice. I drank the chocolade milk and would state it has become more drinkable but not really ice cold, moving them from the regular fridge into the carfridge or moving it out of cooling at the store you buy the drinks at directly into the carfridge will let one avoid having to wait a long time for them to cool down. Adding ice and better isolation will of course cool things down faster and an alternative would be to wait for it to cool down the contents of the container course, like adding drinks at room temperature the day before or such. Altough, another idea would be to have a aluminum container instead of the original plastic ones, like pour them from the original container or bottle into an aluminum 'bottle', this would rapidly increase the cooling of the liquid itself due to the added thermoconduction, as the aluminum casing itself really is ice cold to the touch at this point already. Yet on the other hand while this is a good solution for my daily routine, it adds inconvenience otherwise, unless using drinks already contained in aluminum cans which I must say are plenty here.

Thanks by the way! It's basically just some hobbywork that should hold some long term 'cool' effects.

 

Alright, I came back home now, and while the air temperature has come down to 59 degrees Fahrenheit (15 Celsius) I am astonished to have found that ice has actually formed inside of the freezer (guess I can call it that now ;P)! The aluminum on the inside is literally freezing cold, and should be able to maintain and even create some ice. Will check the temperature again late in the morning tomorrow, when the sun has been back up for a bit, to see what it'll be like then!

 

 

Nice idea.

 

Fridge in a car is always cool (haha) but there are three main issues to putting a fridge in a car.
First is weight, this is the main reason you only see them in large vehicles. You are going to have even more weight with the extra battery. Obviously you have made the decision to add the weight penalty so that parts done.
Second is heat. Don't worry about the body ventilation, you won't really be affecting that, but the fridge expels heat, so you will need to have some sort of vent for that. Fridges have caused many fires in houses and vehicles.
Third is power consumption. You have solved that by adding more weight, so solved again.
Just wanted to make sure people know all considerations for this project.

 

In car fridges have been done in S-Class Mercedes for years. You'd probably have some luck taking a look at those and seeing how they got it to work so well.

 

Thanks, guys! I went to check it right now and saw that it had ran out of power, one full day of power doesn't seem that bad actually. Another step would be to check how fast it can be charged, for this purpose I might switch to an actual starter battery since if I've got the right idea these do charge more quickly than traction batteries (altough I will have to be careful not to destroy my alternator I suppose, maybe use a switch so that it only charges the second battery when the first one is charged enough or something like that). But, while it ran out of power, it is still cold in there and the air temperature is about 68 degrees Fahrenheit (20 Celsius) while it is almost 86 degrees Fahrenheit outside (30 Celsius). Could be interesting to actually check the temperature of the aluminum, this should be far lower than that of the air temperature while the cooler is running, as it actually reached real freezing temperatures by evidence of the ice that formed inside of the fridge.

Edit: Even now, 6 hours after I posted this post, it's still quite a bit colder in there than outside of it despite not being 100% isolated. Another way to power it would be through a solar panel in the panel I have in the trunk, or just on the part above of the fuel tank, the only downside is that a solar panel that could deliver enough power seems to be around $150, and I'm not about to sink a lot of money in this single project. So I'll see what I can do with what I've got, I've got some relays that can handle the amps but I'm not yet sure how to hook it up, I made a diagram but it doesn't account for the batteries being charged separately and hence as far as I can tell will run a very high risk of breaking the alternator as ours are not known to be able to handle much more than what they were originally meant to deal with.

 

I've been trying to think of something to do with that compartment. I'm going to keep this in mind, but keep brainstorming for other cool ideas.